Nowadays mobile communication networks are widely used. These communication networks comprise a plurality of network cells each having at least one base station used to receive and transmit signals from user equipment, e.g. mobile phones or PDAs. A plurality of different environments or systems are known, e.g. GERAN, UTRAN, LTE, E-UTRAN, WCDMA, or WLAN. For ensuring a good performance and in particular a secure data transmission it has to be ensured that all data, data signals, or data packets are received at the intended recipient and at possible relay stations, like base stations of the mobile communication network.
One problem limiting the performance of the data transmission known in the prior art is inter cell interference. In order to reduce the inter cell interference some form of cooperative antenna (COOPA) systems are proposed. From theory significant performance gains with respect to capacity and coverage are known for full cooperating cellular radio systems compared to conventional ones. Due to these large gains, which cannot be achieved with other technologies, as it is known from theory that COOPA systems provide an upper bound for interference limited cellular radio systems. At the same time it is clear that full cooperation is not practical due to required channel state information (CSI) to a huge number of base stations (BS) and accordingly large feedback overhead, especially in case of FDD systems. A further topic is the large amount of data on the backbone network, which might generate a lot of costs in terms of CAPEX and OPEX.
Furthermore, in order to increase the transmission quality so called Hybrid Automatic Repeat Request (HARQ) error correction methods can be employed. When using HARQ the transmitting side consecutively transmits transmission time intervals (TTI) belonging to the HARQ processes. The receive side attempts to decode each process and sends back an acknowledge (ACK) or a non acknowledge (NACK) message or signal, upon which the transmit side either transmits new data in the process and retransmits the data transmitted in the previous cycle of the process, respectively. The receiver soft combines multiple receptions of the same data protocol data unit (PDU).
Within the framework of LTE blanking as well as non blanking HARQ retransmissions have been discussed in the context of MIMO, meaning if two data streams are transmitted and one data stream is already received correctly, this data stream will or will not wait till the HARQ process of the other data stream has been finalized.
For diversity with several transmit antennas based on space time block codes (STBC), HARQ schemes have been proposed, where for retransmission different space time block coding schemes are applied. This might be combined with mapping of data retransmissions to different resource blocks (RBs). The resulting effect is increased diversity gain.
However, these retransmissions may decrease the performance of the communication system, in particular of a cooperative antenna system.
Thus, there may be a need for a communication network element, a method for transmitting data, a communication network system, a program element, and a computer readable medium providing an improved performance of the communication network, in particular in a cooperative antenna system.